Cracked Key is an unlockable consumable in The Binding of Isaac, added in the Repentance DLC.

Activates the effects of Red Key, creating a Red Room adjacent to a viable wall.

Can be created by dropping any trinket in a Boss Room or Treasure Room prior to picking up Dad's Note. Trinkets dropped in these rooms will convert to Cracked Key during the Ascent floors.

This page shows the latest information as of the new Repentance+ (Online Co-op) DLC.
To see information about this consumable for the previous Repentance version, check this page instead.

Open Mom's Chest in the Home level.

Below is the Internal Item Description as shown in-game.
Note that some stat changes are not displayed here. Please see the main description for the full effects.

Cracked Key

• Opens a door to a red room when used next to a valid wall

The following sounds are related to this consumable.

• Check out the consumable description on the external Isaac Wiki.